Pilgering rolling mill



May 27, 1930.

H. IDEL PILGERING ROLLING MILL Filed June 16, 1927 Patented May 27, 1930 UNITED STATES PATENT- OFFICE HERMANN' IDEL, OF DUISBURG, G ERMANY, ASSIGNOR TO DEMAG AKTIIEENGESELL- SCHAFT, F IDUISBURG, GERMANY PILG-ERING ROLLING MILL v Application filed June 16,

In rolling tubes in pilgering rolling mills it is necessary after each rolling operation to ,raise the upper roll in order to enable the several rolling processes involved which fol- 7 low one another in uninterrupted sequence. For this purpose the apparatus must be stopped very precisely at theright time in order to maintain the dimensions of the tube and the thickness of the wall of the tube quite uniform. The present method of stopping the apparatus by hand takes too long, and does not ensure that the upper roll is stopped with the necessary preclsion. 1

According to the present invention it is proposed .to employ a stop which can be set at various posltions yertically, and upon which the crosshead carrying the bearing for "the upper roll comes to rest as it falls. The use of this stop necessitates the employment of a friction element in the drive in order that when the crosshead is arrested, the driving motor may continue to run, without any a so longer acting upon the' adjusting mechanism.

This friction element is so constructed that it operates as a frictional transmitting element-only when the upper roll falls. When the upper roll rises the element acts as a positive transmission element whereby the upper roll is positively raised at the proper time. I

A construction of apparatus according to the invention is diagrammatically illustrated by way of example in the accompanying drawings, in which.

Figure 1 illustrates the complete apparatus inlsi e elevation,

.Figure 2 fig section, r

' Figures 3, 4, 5, and 6 show parts of the "-apparatus on an enlarged scale,

- :v-Figure 7 shows the ilgering mills, and

J g-Figure 8 is a 'detai sectional elevation in is a corresponding longitudinal illustrationof the arrangement of the pres- 1927. 'Serial No. 199,878.

sure spindles and themeans for raising the crosshead.

In the drawings the pilgering rolls mounted in the frame 1 are numbered 2 and 3. The

bearing for the upper roll is suspended in known manner by the rods 4 from the crosshead 6. The crosshead 6 is provided above the frame 1 and engages the screw-threaded spindles 7 which are supported upon and secured to the worm wheels 18 and 19 effecting the rotation of the pressure spindles 8 and have threads of the same pitch but opposite hand to the threads of the said pressure spindles so that as the latter are screwed up or down in the frame 1 the crosshead is moved in the same directions positively by the spindles 7 The spindles 8 are driven by the motor 9 through the clutch 10 whose construction isillustrated in Figures 3, 4 and 5. The drum 12 is keyed upon the motor shaft 11 and is provided with a friction rim 13, which is mounted under spring pressure. The friction rim 13 connects by friction the clutch ring 14 and thus also the shaft 15, to which the clutch ring 14 is connected, with the motor shaft 11. -Upon the shaft 15 are provided the worms 16 and 17. The-worms 16 and 17 engage inthe worm wheels 18 and .19 which in turn act upon the spindles 8 and also upon the spindles 7, the engagement with the spindles 8 being effected by means of extensions of they said spindles which are longitudinally movable through the worm wheel but not relatively rotatable, and may be received into bores formed for the purpose in the spindles 7 The clutch ring 14 (Figures 4 and 6) is provided with spring actuated pawls 20, which, as the motor 9 is driven in operative direction, engage in recesses in the drum 12, and thus cause the upper roll posi-' tively to rise instead of by friction. A stop 22 which can be raised or lowered vertically is provided in the casing 21 mounted on the frame 1; the stop 22 is at its lower part provided with a screw thread, and while itis prevented from rotating by such means as a v groove and key, can only move-axially'upwardly and downwardly. This raising and lowerin of the stop 22 iseffec'ted by means of the chain 23, chain wheel 24 and bevelled the motor 9 drives the spindles 7 and 8 by friction between the clutch members 12 and 14;, whereby the crosshead and therefore also the upper roll, falls until the crosshead comes to lie upon the stop 22. The motor 9 which has not yet come to a standstill may continue to run without hindrance by overcoming the friction in the clutch 12, 14 and then stop. Thus the stopping of the upper roll is ensured with precision at the proper moment.

When the upper roll is again raised the pawls 20 come into operation and provide a positive connection between the motor shaft 11 and the worm shaft 15, so that the roll is positively raised,

1 claim:-

1. Adjusting mechanism for the upper roll of pilgering rolling mills, comprising a frame, superposed rolls in the said, frame, pressure spindles for applying pressure upon the upper roll, and a motor for the operation of the said pressure spindles, the said adjusting mechanism consisting of a crosshead carrying the bearings for the upper roll, and movable from said pressure spindles, an adjustable stop upon which the crosshead comes to lie when the upper roll falls, and a friction coupling between the motor and the pressure spindles adapted to operate as a positive coupling when the upper roll is raised and as a friction coupling when the upper roll is lowered, whereby the motor may continue to run after the crosshead comes to rest upon the stop, substantially as described.

2. Adjusting mechanism for the upper roll of pilgering rolling mills, as set forth in claim 1, having spindles engaged by and serving to move the said crosshead and connected with the said pressure spindles, substantially as described.

3. In adjusting mechanism for the upper roll of pilgering rolling mills, as set forth in claim 1, said adjustable stop comprising a spindle having a screw-thread, the said spindle being constrained to mot e upwardly and downwardly without rotation, a rotatable nut fitting the screw-thread of the said spindle and constrained from axial movement, and means for effecting the rotation of the said nut, substantially as described.

4. In adjusting mechanism for the u per roll of pilgering rolling mills, asset orth in claim 1, said adjustable stop comprising a screw-threaded spindle engaging a rotatable nut constrained from axial movement, a nut provided as a gear wheel, a second gear pressure spindles and efiecting movement 4 thereof, a countershaft for driving the said gear wheels, said counter-shaft receiving movement from the motor by way of the coupling, substantially as described.

6. In adjusting mechanism for the u per roll of pilgering rolling'mills as set orth in claim 1, said coupling comprising relatively movable members engaging one another frictionally, recesses in the engaging surface of one of the said members and one way detent devices carried by the second member and engaging the recesses of the first member, substantially as described.

HERMANN IDEL. 

